A study of the genetics of myopia in collaboration with Dr. Dwight Stambolian is ongoing. Dr. Stambolian is continuing to collect pedigrees with myopia from several populations and has begun a linkage study of this disorder. We have conducted power analyses of the existing pedigrees to determine if they will have adequate power to detect major loci contributing to the susceptibility to myopia and to determine how many more such pedigrees may be necessary to have adequate power to detect genes of moderate effect or major loci in the presence of heterogeneity. This ongoing data collection process has been extended to 4 populations. Dr. Bailey-Wilson also advises Dr. Stambolian and the other data collection sites on the type of family structures that will maximize power for linkage studies. A set of 32 families that have been completely sampled for linkage studies was genotyped in Dr. Stambolian's laboratory for markers in 2 candidate regions on chromosomes 12 and 18 that have been implicated by previous linkage studies as possibly harboring loci for susceptibility to high (extreme) myopia. Dr. Bailey-Wilson and her staff have initiated analyses of these data to determine the possible role of loci in these regions in susceptibility to the milder forms of myopia present in these families. Preliminary results will be presented at the upcoming meeting of the American Society of Human Genetics and a manuscript is in preparation. In addition, a set of completely sampled families from the Ashkenazi Jewish and Amish populations are currently being genotyped for a genome wide screen at the Center for Inherited Disease Research and these data will be analyzed during the next fiscal year.